Report of 8 position valve adj. method
#1090147
10/07/11 10:13 PM
10/07/11 10:13 PM
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Joined: Dec 2009
Posts: 20,646
in a cattle trailer down by th...
Guitar Jones
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Paddle faster! I hear banjo music!
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Paddle faster! I hear banjo music!
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in a cattle trailer down by th...
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Well since I had the intake off I was able to see where the lifter was on the lobe using the 8 position method and it is really accurate. My cam is 276/284 @ .050 solid roller so it's not super radical but it's fairly big.
Now as to my question before about clearance ramps, when I was adjusting the valves #7 int is right after #5 intake. So after adjusting #5 then #7 I went back and checked #5 did not turn the engine any. The lifter is no longer on the base circle but the measured clearance increased .003. So is this extra clearance built into the cam or is it because #6 exh is just about at max lift and it's pushing on the cam and bending it slightly?
"Follow me the wise man said, but he walked behind"
'92 D250 Club Cab CTD, 47RH conversion, pump tweaks, injectors, rear disc and hydroboost conversion.
'74 W200 Crew Cab 360, NV4500, D44, D60 and NP205 divorced transfer case. Rear disc and hydroboost conversion.
2019 1500 Long Horn Crew Cab 4WD, 5.7 Hemi.
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Re: Report of 8 position valve adj. method
[Re: bumps440]
#1090149
10/07/11 10:49 PM
10/07/11 10:49 PM
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Joined: Dec 2009
Posts: 20,646
in a cattle trailer down by th...
Guitar Jones
OP
Paddle faster! I hear banjo music!
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OP
Paddle faster! I hear banjo music!
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Quote:
well this could be Base circle run-out
or an error in the checking method. I DO NOT use any of the Mopar methods.,.. I use the Exhaust open check intake and the intake closing .. check the exhaust
IMO no other accurate method..
That method doesn't work to well with a W head SB as the intake is side loading the exhaust rocker. But I looked at that too and to be honest the 8 position method I think is better as the adjacent rocker is not loaded and so the cam isn't either.
"Follow me the wise man said, but he walked behind"
'92 D250 Club Cab CTD, 47RH conversion, pump tweaks, injectors, rear disc and hydroboost conversion.
'74 W200 Crew Cab 360, NV4500, D44, D60 and NP205 divorced transfer case. Rear disc and hydroboost conversion.
2019 1500 Long Horn Crew Cab 4WD, 5.7 Hemi.
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Re: Report of 8 position valve adj. method
[Re: bumps440]
#1090150
10/07/11 10:52 PM
10/07/11 10:52 PM
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Joined: Feb 2005
Posts: 5,207
Menomonee Falls
DemonDust
master
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master
Joined: Feb 2005
Posts: 5,207
Menomonee Falls
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Quote:
I use the Exhaust open check intake and the intake closing .. check the exhaust
IMO no other accurate method..
That is the method I use
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Re: Report of 8 position valve adj. method
[Re: DemonDust]
#1090151
10/08/11 07:41 AM
10/08/11 07:41 AM
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Joined: Feb 2007
Posts: 6,295
U.S.
moparniac
master
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master
Joined: Feb 2007
Posts: 6,295
U.S.
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I use EOIC and it is the only thing I use... For fun I set the valves using the MOPAR chart and then went back around using EOIC and couldn't believe how much "slop" was between the pushrod and the rocker cup... Kinda scarry actually....
Mopar Performance
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Re: Report of 8 position valve adj. method
[Re: Guitar Jones]
#1090152
10/08/11 08:37 AM
10/08/11 08:37 AM
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Joined: Jan 2003
Posts: 16,928
NC
440Jim
I Live Here
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I Live Here
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Posts: 16,928
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Quote:
Now as to my question before about clearance ramps, when I was adjusting the valves #7 int is right after #5 intake. So after adjusting #5 then #7 I went back and checked #5 did not turn the engine any. The lifter is no longer on the base circle but the measured clearance increased .003. So is this extra clearance built into the cam or is it because #6 exh is just about at max lift and it's pushing on the cam and bending it slightly?
IMO, that is the result of rocker system (shafts, rockers, pushrods) deflection from the valve spring forces. I have seen 0.001-0.002" doing the comparison, but that was with non-roller cam springs.
When done accurately, the position of the cam using both methods is very close and the base circle is much larger than the difference. The big difference IMO, is that people don't accurately set the EOIC method and the rocker system deflects more.
Quote:
Valve lash setting.
MP sticker vs Exhaust Opening, Intake Closing (EOIC).
If you look at the math, the MP sticker method and the E.O.I.C method are very close. And from a lobe profile stand point, the small difference doesn't matter. For example using the MP 0.620" solid cam, the tappet events are very close to this (depending on installed position). I am using the 0.050" tappet lift, because that is about when the eye ball will see it open/close after taking up the 0.028" lash.
Intake opens 34 BTC, closes 69 ABC
Exhaust opens 67 BBC, closes 35 ATC
The EOIC method would get you this:
Set Intake at 67 BBC, which is (180-67)= 113 ATC
Set Exhaust at 69 ABC, which is (180-69)=111 BTC
The MP sticker has the Intake set at 90 ATC
and the Exhaust set at 90 BTC. These are only about 20 degrees different. Have you looked at the base circle of a cam? And the cam is turning half that, so 10 deg on the cam opposite the max lift part is nothing.
Now the rocker shaft deflection issue is real when you are trying to get that last 0.001" setting. So, you really want to set the intake before that 113 ATC point to avoid the exhaust putting pressure on the shaft. And the MP sticker method does it 23 degrees before the EOIC method. Likewise you want to set the exhaust after the 111 BTC, and the MP sticker method does that too, by 21 degrees.
I use both, it just depends... and you can turn that 20 degrees when doing the EOIC method too, but sometimes it requires turning backwards after you see it.
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Re: Report of 8 position valve adj. method
[Re: moparniac]
#1090153
10/08/11 11:22 AM
10/08/11 11:22 AM
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Joined: Jan 2003
Posts: 10,011
Frostbitefalls MN (Rocky&Bullw...
gregsdart
I Live Here
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I Live Here
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Posts: 10,011
Frostbitefalls MN (Rocky&Bullw...
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To get a real accurate reading on where the lash is at the start of each lobe and end of each lobe would take some real work. My assumption is the eight position method may/should be the closest due to being opposite each lobe when you set lash. But the most important thing for being able to catch problems early is to be spot on at each move, no more than about five degrees off the 0 or 180 mark. That will have the cam core loaded by other springs that are part way open, so the deflection in the core is consistant.
I have caught many failures early by seeing a change of .003. Works very well, and most likely has saved me at least one engine/ catostrophic failure.
8..603 156 mph best, 2905 lbs 549, indy 572-13, alky
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Re: Report of 8 position valve adj. method
[Re: gregsdart]
#1090154
10/08/11 06:19 PM
10/08/11 06:19 PM
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Joined: Dec 2009
Posts: 20,646
in a cattle trailer down by th...
Guitar Jones
OP
Paddle faster! I hear banjo music!
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OP
Paddle faster! I hear banjo music!
Joined: Dec 2009
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in a cattle trailer down by th...
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I would have to look again but the rockers I saw under pressure were on the other side. I would think shaft deflection would be more of an issue with the EIOCQUTRD method. 
"Follow me the wise man said, but he walked behind"
'92 D250 Club Cab CTD, 47RH conversion, pump tweaks, injectors, rear disc and hydroboost conversion.
'74 W200 Crew Cab 360, NV4500, D44, D60 and NP205 divorced transfer case. Rear disc and hydroboost conversion.
2019 1500 Long Horn Crew Cab 4WD, 5.7 Hemi.
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Re: Report of 8 position valve adj. method
[Re: Guitar Jones]
#1090155
10/08/11 06:45 PM
10/08/11 06:45 PM
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Joined: Feb 2005
Posts: 5,207
Menomonee Falls
DemonDust
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master
Joined: Feb 2005
Posts: 5,207
Menomonee Falls
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Quote:
I would have to look again but the rockers I saw under pressure were on the other side. I would think shaft deflection would be more of an issue with the EIOCQUTRD method.
If you have individual shafts for each rocker I don't think it's a problem 
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